There are lighting control systems that operate to control multiple zones of lighting through multiple dimming circuits to achieve any one of several desired lighting scenes. These systems include wallbox mounted control units which operate to multiplex digital lighting control information on a communications link. Each wallbox mounted control unit includes zone-intensity actuators which are manipulable to alter the information transmitted by their respective wallbox mounted control unit to vary the lighting intensity of an associated lighting zone. A central control panel (controller) includes a microprocessor adapted to receive and process the multiplexed information transmitted on the link, and re-transmit digital lighting control information, on a second multiplex link, to the dimming circuits. The microprocessor is programmed to assign a preselected dimming circuit to any one of the zone-intensity actuators when that actuator is manipulated according to a predetermined sequence.
There are systems for assigning actuators of a wallbox-mountable lighting control unit to one or more dimmer circuits located in a separate dimming panel for controlling an attached lighting load. The dimmer circuits use a phase control output to adjust the RMS voltage across the load and hence its luminous intensity. A system of this type is commercially available from Lutron Electronics Co., Inc. and is sold under the registered trademark GRAFIK Eye.RTM. dimming panel.
In a GRAFIK Eye system, the output from the wallbox control unit (main unit) is an RS485 digital output. The GRAFIK Eye main units are connected on a four-wire link with each of the main units wired in a daisy chain fashion. Each main unit sends out zone-intensity data over the four-wire link to a control panel located in a dimming panel or relay panel. The information comes into the control panel as a unit address, a zone number, and an intensity value. The control panel takes the unit address, the zone number, and the intensity value, and maps it to the appropriate dimming cards in the GRAFIK Eye dimming panel or a relay in the GRAFIK Eye relay panel. Each dimming/relay card is connected to the control panel through a two-wire harness. The two-wire harness attaches to the dimming/relay card through a multiple pin connector. The first two pins of the connector are for receiving the serial data from the control panel. The other pins of the harness are used to assign an address to each dimming/relay card. This type of system is described in commonly assigned U.S. Pat. No. 5,530,322, "Multi-Zone Lighting Control System," issued to Ference et al. This patent is herein incorporated by reference.
It is known that a wallbox-mountable lighting control system can be adapted to dim a plurality of groups of light sources in a room to any one of a number of different preset levels to achieve a like number of different lighting scenes. Each group of light sources defines a lighting zone and typically each zone is made up of the same type of light source, for example, incandescent lamps, fluorescent lamps, neon lamps, etc. which are all controlled by a phase controlled output. The system includes dimmers for adjusting the respective light level of the different lighting zones, and a display panel for displaying the instantaneous light level of each zone. A suitably programmed microprocessor or the like operates to normalize the system's dimming performance for different types of light sources so that a given change in dimmer setting produces the same change in perceived light level from each of the different types of light sources. The system user inputs the type of light source used in each zone by a software scheme that operates the light level indicators of the display panel in an alternative mode to indicate the various types of light sources. A system of this type is commercially available from Lutron Electronics Co., Inc. and is sold under the registered trademark GRAFIK Eye 3000 Series. This type of system is described in commonly assigned U.S. Pat. No. 5,430,356, "Programmable Lighting Control System With Normalized Dimming For Different Light Sources," issued to Ference et al. This patent is herein incorporated by reference.
Thus, the prior art system controls different loads, but always with a phase controlled output. Separate devices/modules are available for controlling the intensity of different lighting load types which do not use a phase controlled output, such as voltage controlled load types (e.g., 0 to 10 volt sink and 0 to 10 volt source), duty cycle controlled load types (e.g., pulse width modulated (PWM)), and digital signal controlled load types (e.g., digital serial interface (DSI)). However, there is no single device/module that controls the intensity of several different lighting load types where the load types are voltage controlled load types, and/or duty cycle controlled load types, and/or digital signal controlled load types. Therefore, a need exists for a device / module that overcomes the drawbacks of the prior art and controls the intensity of different load types including voltage controlled load types, duty cycle controlled load types, and digital signal controlled load types.